Purification of ATP-binding Cassette Transporter A1 and Associated Binding Proteins Reveals the Importance of β1-Syntrophin in Cholesterol Efflux

Abstract

ATP-binding cassette transporter A1 (ABCA1) plays a critical role in HDL cholesterol metabolism, but the mechanism by which it transports lipid across membranes is poorly understood. Because growing evidence implicates accessory proteins in this process, we developed a method by which proteins interacting with the intact transporter could be identified. cDNAs encoding wild-type ABCA1 and a mutant lacking the C-terminal PDZ binding motif ABCA1 and the proteins with ABCA1 by with the PDZ this and this in and in cholesterol by in ABCA1 ABCA1 and a PDZ with the ABCA1 the and the in which ABCA1 ATP-binding cassette transporter A1 (ABCA1) plays a critical role in HDL cholesterol metabolism, but the mechanism by which it transports lipid across membranes is poorly understood. Because growing evidence implicates accessory proteins in this process, we developed a method by which proteins interacting with the intact transporter could be identified. cDNAs encoding wild-type ABCA1 and a mutant lacking the C-terminal PDZ binding motif ABCA1 and the proteins with ABCA1 by with the PDZ this and this in and in cholesterol by in ABCA1 ABCA1 and a PDZ with the ABCA1 the and the in which ABCA1 cholesterol is critical a in cholesterol in which cholesterol is cassette transporter cassette transporter this is in with a by in the ABCA1 transporter cholesterol a in and Because HDL with and in the in the a cholesterol is a critical role in cholesterol be a ABCA1 the and cholesterol ABCA1 is with the a the a role in this the binding the transporter by a is with in the ABCA1 ABCA1 and the the transporter and the cholesterol by a and the ABCA1 could a role in the the cholesterol proteins in ABCA1 by a a the ABCA1 a PDZ motif in the the the this motif be ABCA1 PDZ proteins in 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